Hydrophilic organopolysiloxane composition for use as dental impression material

Abstract

A hydrophilic organopolysiloxane composition of the hydrosilylation reaction cure type for use as dental impression material is characterized by comprising as essential components (A) a diorganopolysiloxane having at least 0.1 silicon-bonded alkenyl group in a molecule, (B) a liquid or solid organopolysiloxane having average compositional formula (1), comprising SiO 2 units and R 3 SiO 1/2 units (R is a monovalent hydrocarbon, alkoxy or hydroxyl group) and having a viscosity of at least 10 mPa-s at 23° C., (C) an organohydrogenpolysiloxane having at least two silicon-bonded hydrogen atoms in a molecule, (D) a hydrosilylation catalyst, and (E) a polyether having average compositional formula (2).

1. A hydrophilic organopolysiloxane composition of the hydrosilylation reaction cure type for use as dental impression material, comprising as essential components,
 (A) a diorganopolysiloxane having at least 0.1 silicon-bonded alkenyl group in a molecule, 
 (B) a liquid or solid organopolysiloxane having the average compositional formula (1):
   R p SiO (4-p)/2   (1)
 
 
 wherein R is each independently a substituted or unsubstituted monovalent hydrocarbon group, alkoxy or hydroxyl group, 0.1 to 80 mol % of the entire R being alkenyl, and p is a positive number satisfying 1≦p<2, said organopolysiloxane comprising SiO 2  units and R 3 SiO 1/2  units and having a viscosity of at least 10 mPa·s at 23° C., 
 (C) an organohydrogenpolysiloxane having at least two silicon-bonded hydrogen atoms in a molecule, 
 (D) a hydrosilylation catalyst, and 
 (E) a polyether having the average compositional formula (2):
   R 1 O(C 2 H 4 O) m (C 3 H 6 O) n R 1   (2)
 
 
 wherein R 1  is a group C 3 H 6 SiR 2   k (OR 2 ) 3-k  or a monovalent hydrocarbon group, R 2  is a monovalent hydrocarbon group, k is 0, 1, 2 or 3, a plurality of R 1  and a plurality of R 2  may be the same or different, at least two of R 1  and R 2  are alkenyl, m is an integer of 0 to 100, n is an integer of 0 to 350, and m+n is an integer of 3 to 350, 
 said component (E) being present in an amount of 10 to 100 parts by weight per 100 parts by weight of components (A), (B), and (C) combined. 
 
     
     
       2. The hydrophilic organopolysiloxane composition for use as dental impression material of  claim 1 , further comprising as an essential component (F) a diorganopolysiloxane containing at least 3 mol % of diphenylsiloxane units or at least 6 mol % of methylphenylsiloxane units, and free of silicon-bonded alkenyl groups in a molecule. 
     
     
       3. The hydrophilic organopolysiloxane composition for use as dental impression material of  claim 1 , wherein component (E) is present in an amount of 10 to 50 parts by weight per 100 parts by weight of components (A), (B), and (C) combined. 
     
     
       4. The hydrophilic organopolysiloxane composition for use as dental impression material of  claim 1 , wherein the organopolysiloxane as component (B) is a resinous copolymer comprising SiO 2  units, R 3 SiO 1/2  units, R 2 SiO 2/2  units and RSiO 3/2  units wherein R is as defined above, the molar ratio of R 3 SiO 1/2  units to SiO 2  units being from 0.5:1 to 1.5:1, and R 2 SiO 2/2  units and RSiO 3/2  units being contained in a total amount of 0 to 50% based on the total weight of the organopolysiloxane resinous copolymer. 
     
     
       5. The hydrophilic organopolysiloxane composition for use as dental impression material of  claim 1 , wherein the amount of organopolysiloxane (B) blended is 5 to 50 parts by weight per 100 parts by weight of component (A). 
     
     
       6. The hydrophilic organopolysiloxane composition for use as dental impression material of  claim 1 , wherein the organohydrogenpolysiloxane as component (C) is blended in such an amount as to provide 0.1 to 4.0 moles of silicon-bonded hydrogen atoms per mol of silicon-bonded alkenyl groups in components (A) and (B). 
     
     
       7. The hydrophilic organopolysiloxane composition for use as dental impression material of  claim 2 , wherein the diorganopolysiloxane as component (F) is blended in an amount of 1 to 50 parts by weight per 100 parts by weight of component (A). 
     
     
       8. The hydrophilic organopolysiloxane composition for use as dental impression material of  claim 2 , wherein component (E) is present in an amount of 10 to 50 parts by weight per 100 parts by weight of components (A), (B), and (C) combined. 
     
     
       9. The hydrophilic organopolysiloxane composition for use as dental impression material of  claim 2 , wherein the organopolysiloxane as component (B) is a resinous copolymer comprising SiO 2  units, R 3 SiO 1/2  units, R 2 SiO 2/2  units and RSiO 3/2  units wherein R is as defined above, the molar ratio of R 3 SiO 1/2  units to SiO 2  units being from 0.5:1 to 1.5:1, and R 2 SiO 2/2  units and RSiO 3/2  units being contained in a total amount of 0 to 50% based on the total weight of the organopolysiloxane resinous copolymer. 
     
     
       10. The hydrophilic organopolysiloxane composition for use as dental impression material of  claim 2 , wherein the amount of organopolysiloxane (B) blended is 5 to 50 parts by weight per 100 parts by weight of component (A). 
     
     
       11. The hydrophilic organopolysiloxane composition for use as dental impression material of  claim 2 , wherein the organohydrogenpolysiloxane as component (C) is blended in such an amount as to provide 0.1 to 4.0 moles of silicon-bonded hydrogen atoms per mol of silicon-bonded alkenyl groups in components (A) and (B).